1. Field of the Invention
The invention relates generally to shelf systems for audio and video components and more particularly to apparatuses and methods for construction of anti-vibration shelf systems.
2. Relevant Art
There are several steps in high quality audio/video reproduction. Starting from a high quality recorded media, CD or LP, the signal transfers from a player to a pre-amplifier and amplifier and others to speakers. This is a serial transfer and requires a well matched high performance component system for a high quality reproduction. Vibration interferes with this transfer and distorts the signals. Vibration of all sorts is the greatest detriment to high quality reproduction of music. The source of vibration may be external to the audio system, such as the noise from appliances like a refrigerator, forces resulting from movement such as a person or animal running in the room, or the wind or may be internal to the audio/video system such as speakers or the component's power. Regardless of the source, vibration distorts analogue and digital signals and causes loss of details and harmonics.
Vibration interfering with audio/video reproduction occurs at various frequencies. Human ears can generally detect such noises to about 20 KHz. While the audio perception may be limited, higher frequency vibration may also interfere with the audio or video components' performance.
High-quality audio/video reproduction requires a well matched system consisting of a high performance audio/video source, amplifier, speakers, cables and a rack to house everything. Like a chain, all components of the system contribute to a high performance audio/video experience. The system is only as good as its weakest link. No matter how good the CD player or the speakers, if the rack is not dissipating vibration, one will not experience the ultimate in audio/video reproduction.
The relationship between a system's dynamic properties and its response to an arbitrary vibration force F can be represented as:MX″+CX′+KX=F 
Where X is displacement (motion)of the system, X′ velocity and X″ is acceleration and, M represents mass, C damping and K stiffness of the system. A properly designed high-performance anti-vibration rack or shelf will virtually eliminate vibration, a significant detriment to music reproduction.
The selection of materials may also impact the performance of a system. Materials that minimize vibration exist. An example of such is carbon fiber composites.
Carbon fiber generally refers to carbon filament thread, or to felt or woven cloth made from those carbon filaments. The term carbon fiber is also used to mean any composite material made with carbon filament, such a material is sometimes also referred to as graphite-reinforced plastic.
Each carbon filament is made out of long, thin filaments of carbon sometimes transferred to graphite. A common method of making carbon filaments is the oxidation and thermal pyrolysis of polyacrylonitrile (PAN), a polymer used in the creation of many synthetic materials. Like all polymers, polyacrylonitrile molecules are long chains, which are aligned in the process of drawing continuous filaments. When heated in the correct conditions, these chains bond side-to-side (ladder polymers), forming narrow graphene sheets which eventually merge to form a single, jelly roll-shaped or round filament. The result is usually 93-95% carbon. Lower-quality fiber can be manufactured using pitch or rayon as the precursor instead of PAN. The carbon can become further enhanced, as high modulus, or high strength carbon, by heat treatment processes. Carbon heated in the range of 1500-2000° C. (carbonization) exhibits the highest tensile strength (820,000 psi or 5,650 MPa or 5,650 N/mm2), while carbon fiber heated from 2500 to 3000° C. (graphitizing) exhibits a higher modulus of elasticity (77,000,000 psi or 531 GPa or 531 kN/mm2).
There are several categories of carbon fibers: standard modulus (250 GPa), intermediate modulus (300 GPa), and high modulus (>300 GPa). The tensile strength of different yam types varies between 2000 and 7000 MPa. The density of carbon fiber is 1750 kg/m3.
Precursors for carbon fibers are PAN, rayon and pitch. In the past rayon was more used as a precursor and still is for certain specialized applications such as rockets and specific aerospace application. Carbon fiber filament yams are used in several processing techniques: the direct uses are for prepregging, filament winding, pultrusion, weaving, braiding and the like.
The filaments are stranded into a yam. Carbon fiber yam is rated by the linear density (weight per unit length=1 g/1000 m=tex) or by number of filaments per yam count, in thousands. For example 200 tex for 3,000 filaments of carbon fiber is 3 times as strong as 1,000 carbon fibers, but is also 3 times as heavy. This thread can then be used to weave a carbon fiber filament fabric or cloth. The appearance of this fabric generally depends on the linear density of the yam and the weave chosen. Carbon fiber is naturally a glossy black but colored carbon fiber is also available.
Carbon fiber may be used to reinforce composite materials, particularly the class of materials known as carbon fiber reinforced plastics. This class of materials is often used demanding mechanical applications. Carbon fiber's unique properties such as high stiffness, high strength, high damping, low density, and corrosion resistance are ideal for demanding applications. Carbon fiber/epoxy composites have mechanical properties such as the stiffness and strength of steel, and damping of 10 times more than aluminum at 30% lower density.
While non-polymer materials can also be used as the matrix for carbon fibers, due to the formation of metal carbides (i.e., water-soluble AIC), bad wetting by some metals, and corrosion considerations, carbon is used less frequently in metal matrix composite applications.
As such, there is a need for an apparatus that minimizes the effects of vibration on audio and video components. The present invention present a novel approach to the design, material selection and construction of an isolation rack that dampens vibration at all frequencies, dissipates the vibration energy and as a result, isolates the high performance audio/video source from deadly vibration resulting in high quality audio/video reproduction.